Bob Savage
Python on a Mac running macOS is in principle very similar to Python onany other Unix platform, but there are a number of additional features such asthe integrated development environment (IDE) and the Package Manager that areworth pointing out.
5.1. Getting and Installing Python¶macOS used to come with Python 2.7 pre-installed between versions10.8 and 12.3.You are invited to install the most recent version of Python 3 from the Pythonwebsite.A current “universal2 binary” build of Python, which runs natively on the Mac’snew Apple Silicon and legacy Intel processors, is available there.
What you get after installing is a number of things:
A Python 3.12 folder in your Applications folder. In hereyou find IDLE, the development environment that is a standard part of officialPython distributions; and Python Launcher, which handles double-clicking Pythonscripts from the Finder.
A framework /Library/Frameworks/Python.framework, which includes thePython executable and libraries. The installer adds this location to your shellpath. To uninstall Python, you can remove these three things. Asymlink to the Python executable is placed in /usr/local/bin/.
Note
On macOS 10.8-12.3, the Apple-provided build of Python is installed in/System/Library/Frameworks/Python.framework and /usr/bin/python,respectively. You should never modify or delete these, as they areApple-controlled and are used by Apple- or third-party software. Remember thatif you choose to install a newer Python version from python.org, you will havetwo different but functional Python installations on your computer, so it willbe important that your paths and usages are consistent with what you want to do.
IDLE includes a Help menu that allows you to access Python documentation. If youare completely new to Python you should start reading the tutorial introductionin that document.
If you are familiar with Python on other Unix platforms you should read thesection on running Python scripts from the Unix shell.
5.1.1. How to run a Python script¶Your best way to get started with Python on macOS is through the IDLEintegrated development environment; see section The IDE and use the Help menuwhen the IDE is running.
If you want to run Python scripts from the Terminal window command line or fromthe Finder you first need an editor to create your script. macOS comes with anumber of standard Unix command line editors, vimnano among them. If you want a more Mac-like editor,BBEdit from Bare Bones Software (seehttps://www.barebones.com/products/bbedit/index.html) are good choices, as isTextMate (see https://macromates.com). Other editors includeMacVim (https://macvim.org) and Aquamacs(https://aquamacs.org).
To run your script from the Terminal window you must make sure that/usr/local/bin is in your shell search path.
To run your script from the Finder you have two options:
Drag it to Python Launcher.
Select Python Launcher as the default application to open yourscript (or any .py script) through the finder Info window and double-click it.Python Launcher has various preferences to control how your script islaunched. Option-dragging allows you to change these for one invocation, or useits Preferences menu to change things globally.
5.1.2. Running scripts with a GUI¶With older versions of Python, there is one macOS quirk that you need to beaware of: programs that talk to the Aqua window manager (in other words,anything that has a GUI) need to be run in a special way. Use pythonwinstead of python to start such scripts.
With Python 3.9, you can use either python or pythonw.
5.1.3. Configuration¶Python on macOS honors all standard Unix environment variables such asPYTHONPATH, but setting these variables for programs started from theFinder is non-standard as the Finder does not read your .profile or.cshrc at startup. You need to create a file~/.MacOSX/environment.plist. See Apple’sTechnical Q&A QA1067for details.
For more information on installation Python packages, see sectionInstalling Additional Python Packages.
5.2. The IDE¶Python ships with the standard IDLE development environment. A goodintroduction to using IDLE can be found athttps://www.hashcollision.org/hkn/python/idle_intro/index.html.
5.3. Installing Additional Python Packages¶This section has moved to the Python Packaging User Guide.
5.4. GUI Programming¶There are several options for building GUI applications on the Mac with Python.
PyObjC is a Python binding to Apple’s Objective-C/Cocoa framework, which isthe foundation of most modern Mac development. Information on PyObjC isavailable from pyobjc.
The standard Python GUI toolkit is tkinter, based on the cross-platformTk toolkit (https://www.tcl.tk). An Aqua-native version of Tk is bundled withmacOS by Apple, and the latest version can be downloaded and installed fromhttps://www.activestate.com; it can also be built from source.
A number of alternative macOS GUI toolkits are available:
PySide: Official Python bindings to theQt GUI toolkit.
PyQt: AlternativePython bindings to Qt.
Kivy: A cross-platform GUI toolkit that supportsdesktop and mobile platforms.
Toga: Part of the BeeWare Project; supports desktop, mobile, web and console apps.
wxPython: A cross-platform toolkit thatsupports desktop operating systems.
5.5. Distributing Python Applications¶A range of tools exist for converting your Python code into a standalonedistributable application:
py2app: Supports creating macOS .appbundles from a Python project.
Briefcase: Part of the BeeWare Project; a cross-platform packaging tool that supportscreation of .app bundles on macOS, as well as managing signing andnotarization.
PyInstaller: A cross-platform packaging tool that createsa single file or folder as a distributable artifact.
5.6. Other Resources¶The Pythonmac-SIG mailing list is an excellent support resource for Python usersand developers on the Mac:
https://www.python.org/community/sigs/current/pythonmac-sig/
Another useful resource is the MacPython wiki:
https://wiki.python.org/moin/MacPython